Best of web video: Halloween special

October's pick of web video features 10 science and tech shockers guaranteed to tingle your spine. Watch in terror as slime mould overruns Tokyo. Cower before the most awesome destructive force in the universe - a supernova. Watch out for all the usual Halloween favourites: bats, snakes, crows, skeletons and body parts. And for all you zombies out there, the number 1 clip promises to be delicious.